This series has a number of aspects especially peculiar to it. Many of them were later retconned to fit better into the Expanded Universe (EU). Notable among them are:

Lando Calrissian's noteworthy achievements of saving or at least befriending no less than three highly advanced civilizations. Two of them (Sharu and Oswaft) were never mentioned again in EU except several roleplaying game supplements and resource books. However, the third civilization—the Silentium—appeared in brief excerpts from the Han Solo Trilogy when the droid character Vuffi Raa appeared and was mentioned as joining his impressively advanced comrades. The Silentium were also much later retconned to be one of the two warring factions provoking Yuuzhan Vong to hate technology.

Lando Calrissian's stingbeam-type blaster pistol was designed for the trilogy and never mentioned again.

The weapons present on the Imperial starships in the third book are never mentioned anywhere else in EU.

The Millennium Falcon's arsenal has different weapon placement from the movies and other books. However, the second tome of the Han Solo Trilogy, The Hutt Gambit, reveals that in fact quad laser cannons were originally installed in peculiar way and Han Solo, after winning the Falcon, changed their placement for both better range and greater cover area of fire.

The cards and game mechanics of sabacc were first introduced in these books. The full game and rules were later presented in West End Games' Crisis on Cloud City adventure, loosely based on the game described in the Lando books but with some variations (such as dropping the fact that fives are wild, a nonsensical rule anyway in a game where the total sum of a player's cards determines victory). Most subsequent sabacc appearances in the EU followed the West End Games rules. It was later stated that the game played throughout this trilogy is simply a variant called Centran Sabacc.

Names of most of the mentioned planets had numbers, unlike most of planets mentioned elsewhere. However, all of the planets mentioned are located in a galactic region called Centrality. This could mean that Centrality used its own naming convention.